Lifting-jack.



J. GORYELL. LIFTING JACK.

APPLICATION FILED APB.1, 1912.

Patented 0G13. 14. 1913.

LYG,

JOHN GORYELL, or oomcEL'L, MICHrGAN.

LIFTING-S'ACK.

Application ledAp'ril 1,

Be. it known that l. JOHN CORYELL a citizen of the'Un-itedl States, residing at ory'ell. iii the -county :of Mackinac and State ofI lilichigan, have invented new and useful linproveinents in Lifting-Jacks, of vwhich thel following is a specification.

This invention'relates to lifting jacks and the object of the invention is to' provide a teleseoping screw jack with ineaus whereby. the head niay b e extended 'lroin the base y 'ith' a reciprocating inoveinem ot the lever..

Further objects of this invention will appear as the following specitic description is' read inconnectfion with the accompanying drawing,"which 'l'oiins apart ot'this appli- 'cation,a'nd in whichzfl Figure'l is'a side elevation. Fig. iQ is a verticalsection'. Fig. 3 is' a horizontal section on the line 3-3 of Fig. 2. Fig. 1l is a similar section on the line A4 4 of Fig. 2.

Referring more particularly to the drawing, 1 represents 'a suitable base which is provided with-a circular head 2 having a ratchet upper face- Band a central screw threaded bore4. Threaded into the bore t is a inain jack screw 5 which has s-lidably1 'mounted thereon'aflockingvnut or nieiiiber (S having 'aratchetundersurface 7 to coact lwith the ratchetsurface 3 of lthe head Q. This'lock-ing nut or collar G is provided with ai'iinternal gib or key 8 which is seated in the -longitudinal groove 9 orined in the screw vso as to cause the locking nut to rotate withtlie inain'j ack screw lVhen the jack screw 5 is rotated inthe proper direction to unscrew it from the base 1, the locknut 6 willrotate wit-h the screw and ride up upon the same to disengage its ratchet teeth froni the teeth 3.

y rl `he upper end of the screw 5 is provided with a circular ratchet head 10 und the. screw is hollowed out and threaded so as to receive the auxiliary ljack screw 11. rl`he head1() is provided with. ratchet teeth 12 arranged vinposition to the teethV 13 and adapted*l to be engaged byyratchet teeth 13- arranged in position to the ratchet teeth 7 and carried by the auxiliary locking collar le which is ably mounted upon the auxiliary screw 11'. This collar is'also provided with an internal vgib or'key 15' which engages the longitudinal channel or groove 16 so as to cause the lock lnut 14 to rotate -with the screw 11 and yet per'mitthesame to slide vertically on the Specification of Letters Patent.

Vthe screw 5.

slid- Patented @et 11, il 913.

1912. seriai No. 687,833.

'screw 11 being` provided-with a lc'i hand rlhis order'iiiay be reversed il'- thread. ound to-be desirable. rlhe locking nuts ii and let are provided with set screws 21 which are adapted to hold the locking collars in elevated position upon the screws so that these screws in'ay be backed into their respective holders.

.ln operating the device, it .the lever tl lic forced' away frein the spectator the screw 5 will be unscrewediroin the base l. the lock nut t3 riding idly over the head 2 and the lock nut 14 positively engaging the head 10 to rotate the screw. llpon nioveinent ot' the lever in the opposite direction. the lock nui 6 will loch with the liat Q while the lock nut 14; will ride idly-over the-head 1t? and the screw 11 will uiiscrew ifroin the bore in To lower the screws into their. refpective holders. it is only iim'essary to slide the locliiii its vertical groove u-pon the screws and hohl theui in elevated positions by means of the set screws 2l.

what is clainied iss 1. ln combination. a base. a screw threaded into the base. a second screw threaded into the first screw. a lever connected to the second screw. and nicans to alternately and automatically lock one screw'and permit the rotation of the other screw upon a reciprocating inovenient oi the level'.

2. In combination. a base. ascrcw threaded ther-cinto. a second screw threaded into the first vscrew and having its threads running in opposite directionstothe threads` of the first screw, a lever connected top the second screw. and opposite ratchet conucctions between the irst screw and the hase and between the second screw vand the iii-st screw.

In testimony whereof 1 atlix my signature in presence of two witnesses.

' JHNCRYELL. 'Witnesses Ania-iai' Bosma', fiigvir: A. llossaox. 

